A NASA satellite lifted off early Saturday on a three-year mission to track the amount of water locked in soil, which may help residents in low-lying regions brace for floods or farmers prepare for drought conditions.

It'll take some time before project managers know if the satellite successfully separated from the rocket and unfurled its solar panels to start generating power.

"I'm extremely eager" to start the mission, project manager Kent Kellogg of the NASA Jet Propulsion Laboratory, said earlier this week at a pre-launch briefing.

During the first stage of the launch, flight commentator Steve Agid said the performance "continues to look good."

Once the satellite reaches the desired orbit 430 miles high, engineers will spend two weeks checking out the two instruments, which will measure moisture in the soil every several days to produce high-resolution global maps.

Scientists hope data collected by the satellite, the latest to join NASA's fleet of Earth-orbiting satellites, will improve flood forecasts and drought monitoring.

Currently, drought maps and flash flood guidance issued by the federal government are based on computer modeling. SMAP will take real-time measurements that can be incorporated into forecasts, said Dara Entekhabi, mission science team leader from the Massachusetts Institute of Technology.

The rocket was supposed to fly earlier this week, but high winds and technical problems kept it grounded.

JPL manages the $916 million mission, which is designed to last at least three years.

Besides the satellite, the rocket also carried three research nanosatellites for JPL, Montana State University and California Polytechnic State University. More than 100 university students took part in designing and building the tiny satellites known as CubeSats.